Magazine valve for moving picture projectors



Feb. 16, 1932. A. J. HOLMAN 45350 MAGAZINE VALVE FOR IJOVING PIG'IfgREFROJECTORS Filed AugrS} 1927 2 Sheets-Sheet 1 Feb. 16, 1932. A. J.HOLMAN MAGAZINE VALVE FOR MOVING PICTURE PROJECTORS Filed Aug. 8, 1927 2Sheets-Sheet 2 Patented Feb. 16, 1932 UNITED STATES ARTHUR J. HOLMAN, FBOSTON, MASSACHUSETTS MAGAZINE VALVE FOR MOVING PICTURE PROJECTOR-SApplication filed August 8, 1927.

My invention relates to the guideway or valve, so called, through whichfilm is led either from the magazine containing the unwinding reel offilm into the projector, or

.3 from the projector into the magazine containing the take-up reel. Ithas been the special object of my invention to so design and constructthe magazine valve that, should the film in the projector start to burn,the fire will be choked and extinguished within the magazine valvebefore it can extend to the reel of film and cause a serious fire. Ithas been my aim to accomplish this object while at the same time soconstructing the valve that the film may be easily threaded through thedevice when putting it in position for projecting the film pictures.

My device may be best understood by reference to the accompanyingdrawings, in

which Fig. 1 is a side view of a projector of the type shown in myPatent No. 1,584,098 dated May 11, 1926, showing upper and lowermagazine valves connected therewith and also connected respectively toupper and lower magazines of conventional type for containing the reelsof film. These magazines for containing the reels of film are shownpartly broken away and the framework for supporting the magazines is notshown.

Fig. 2 is a vertical section of a part of the top magazine and itsvalve.

Fig. 3 is a top view of the bottom side plate H of the valve shown inFig. 2 showing the inwardly projecting plate integral therewith arrangedto underlie the film.

Fig. 4 is a cross-section on line 44 of Fig. 1.

Referring now more specifically to the drawings in which like referencenumbers indicate like parts, A is the upper magazine, A the lowermagazine. B is the projector. Each valve connecting magazines A and Awith the projector B is a metallic casting having a side wall C, and topand bottom walls D and E respectively (see Figs. 2 and l). From the topwall D there extend inwardly ribs 03 and (l and from the bottom wall Ethere extend inwardly ribs e and 0 The open front of the valve is closedby an upper Serial No. 211,282.

cover plate F and a lower cover plate G attached by screws H which enterthreaded holes h.

The cover plate F is provided with an integral inwardly projecting platef which exll tends across and adjacent the extremities of the ribs (Zand (Z and the cover plate G is provided with an inwardly projectingplate 9 which extends inwardly and across the tops of the ribs 6 and 6The plates and g are separated by a space of about onesixteenth of aninch, thereby permitting a slight clearance for the film I as will beobserved by reference to the drawings. The plates f and g are ofsubstantial thickness and are formed of metal castings as above stated.As these plates f and g are made integral with the cover plates F and G,respectively, there is presented to the film, in close proximity to eachside thereof, a considerable mass of metal, the use and advantage ofwhich will be later explained.

Suitable rollers are provided between which the film may be run andguided evenly between the plates 7 and 9. For the upper magazine valve,as the roll in this magazine is usually on th unwinding reel, Ipreferably provide rollers J and K, one of which will engage the filminitially. As shown in Fig. 2 of the drawings, roller J is initiallyengaged as the film is being unwound, but in occasional instances wherethe film is led off the lower side of the reel instead of off the top itwould contact with roller K. The roller L always supports and guides thelower side of the film whether or not that side of the film is incontact with the roller K. In the lower valve the lead of the film fromthe valve to the reel is always the same, and therefore in this valvethe roller K is omitted. The rollers are suitably cut away in the usualmanner so as to avoid frictional contact with the picture area of thefilm.

On the projector side of each valve there are provided a pair ofoppositely placed rollers M and N to support and guide the oppositesides of the film strip so that the film strip will not drag on eitherthe plate f or the plate g. All of the rollers are provided withsuitable annular lugs p upon their ends, which lugs upon one end enterand revolve in holes in the side wall C, While those upon the other endenter and revolve in opposite holes in cover plates F or G.

It will be observed in Fig. 4 that the film I setsuwell into the slotformed between the plates f and 9 so that its edge nearer the slotopening is located well within the slot. Should the film catch fire, asoccasionally happens, because of heat from the condenser beam within theprojector, the flame will quickly travel to that part of the film whichis located between plates f and g, and when the flame has reached thispoint the heat conducting properties of the metallic plates f and 9 willquickly reduce the temperature of the flame below the ignitiontemperature of the film, and at the same time the fire Will becomechoked for lack of oxygen within the confined space between these platesso that r the fire will be quickly and completely extinguished before itcan pass on to ignite the main body of film in the adjacent magazine.

I have thus provided a simple and eifective means for choking andextinguishing a film fire before it can become dangerous while at thesame time I have provided a simple valve apparatus through which thefilm can be easily inserted from the side without diificultmanipulation, and may run without contact with the film on the picturearea. 7

Having thus fully described my invention, What I claim is, r

1. In a device of the character specified,

the combination of a casing connecting a film' magazine with a projectormechanism and being structurally exterior to both, said casing beingopen at one side, means within said casing for positioning the path ofthe film, a pair of cover plates mounted upon the open side of saidcasing in slightly spaced relation whereby an opening is provided alongthe path of the film and plates projecting inwardly from each of saidcover plates along said opening ina manner whereby there is formed arestricted passage for film, said cover plates being of substantialthickness.

2. In a magazine valve arranged to connect a film magazine and projectormechanism, the combination of a cast casing located" exterlor to saidmagazme and sald mechanism, a plurality of rollers enclosed in saidcasing, said rollers having fixed axes of rotation and serving primarilythe purpose of fixing the path of film through said magazine valve, anda pair of heavy metallic plates arranged and positioned to parallel thepath of the film and to be in close proximity theretothroughout a largeportion of said fixed path of said film. V V I ARTHUR J. HOLMAN.

